Radioreceiver



March 20, 1928.

W. M. BRUCE. J R

RADIORECEIVER Filed Sept. 3, 1925 2 Sheets-Sheet 2' I V/VIIIIIIII Pffl V' m VENTOR ATTORNEYS Patented Mar. 20, 1928 UNITED STATES WILLIAM M. BRUCE, JR., SPRINGFIELD, OHIO.

RADIOBECEIVEB.

Application filed September 3', 1925'. Serial No..54,283.

My invention relates to imp'rovementsin radio receivers, it more particularly relating to an attachment for that type of receiver which employs a sound amplifying device in the nature of a comparatively large coneshaped diaphragm.

The object of my invention is to provide an arrangement for equipping such a type of receiver with ear reception devices together with means in one form of myinvention for placing the amplifying diaphragm in inoperative condition so that the reception can be had only through the ear pieces.

In the accompanying drawings:

Fig. l is a rear view of a radio reception device embodying my improvements.

Fig. 2 is an inverted view of a portion of the base.

Fig. 3 is a section on the line 3-3 of Fig. 2.

Fig. 4 is a sectional view on the line 4-4 of Fig. 1. Fig. 5 is a. sectional view showing a modification of my invention.

of the diaphragm.

Fig. 7 is a side view of the sound box shown in Fig. 4. Fig. 8 is a section on the line 8-8 0t Fig. 7. 7 Referring to the drawings, 1 represents a base having a vertical standard 2 to which is secured a supporting member 3 having its upper end widened into the form of a table 4 to which is secured a rectangular frame consisting of side bars 5, a forward cross bar 6 and a rear cross bar 6. This rectangular frame carries the audio receiving mechanism consisting of a permanent magnet 7, coils 8 and armature 9 of any usual type, the armature 9 being supported by a thin metallic plate 9 secured to the cross bar 6. An amplifying member in the form of a cone-shaped disk 11 is seated in a ring 11 carried on arms 5 which are secured to and project from the sidebars 5 and the ring is further attached to the supporting standard 2 in the usual manner so as to provide three points of support for the ring. The apex of the cone is provided with a sleeve 12, this sleeve having cone-shaped metallic plates 13 which embrace and are secured to in any suitable way that portion of the cone surrounding the apex, with a portion of the sleeve located in the apex. The sleeve car- Fig. 6 is a sectional view through the apex ries a set-screw 14:.by meansof which the outer end of 'a rod 15 may be secured tothe apex of the cone, the inner end 'ofthis rod being secured to the armature member 9. The bore of the sleeve is considerably larger than the diameter of the rod so that when the rod is disconnected it can move freely and have no vibratoryeil'ect uponthe cone. This cone constitutes an amplifying device for a receiver ofthe type generally known as aloud speaker. i

Secured to the cross-bar 6 is the rear half 16 of a sound chamber, the forward half being indicated at 16 and being secured to the rear half by screws, as shown, or other suitable fastening devices. Clamped between the two halves ofthis sound chamber is a diaphragm 17. The rod 15 passes through the walls or the sound chamber and through the center of the diaphragm 17, being secured to the diaphragm by soldering or otherwise. A nipple 18 is secured to the sound chamber and communicates with the interior thereof and a second nipple 19 is secured to the standard 2, the two nipples being connected by a tube 20. A conduit, indicated by dotted lines at 21, communicates with the lower nipple l9 and passes through the standard 2 and base 1 where it is divided into three branches 21, as shown in Fig. 2. Each branch, as indicated in Fig. 3, communicates with a connector 22 located in the base which has a spring pressed valve in the nature of a ball 23 pressed to its seat by the coil spring 24. Each one of these connectors provides a point of attachment for the slip connection 23 of a tube 24 which leads to an ear piece 25 of well known form, this slip connection pressing the ball valve from its seat when inserted. i

In Fig. 5 there is shown a modification in which the soundchamber isformed by the cone 11 and a circular plate 26 which is supported by a bracket 27 secured to the cross bar 6 with its edge in close. proximity to the cone 11. The rod 15 passes through an aperture in the disk 26 and in this case will be permanently connected to the apex of the ported upon said base, a cone shaped diaphragm of an amplifying character having its apex connected with said mechanism and supported from said base, a sound chamber located on one side of said diaphragm, and a conduit leading from said sound chamber to a connector carried by said base, said connector being arranged to receive the tube of an ear reception member.

2. In a radio receiving device, audio receiving mechanism comprising an armature, a sound chamber, a diaphragm in said sound chamber, a second larger cone-shaped diaphragm of an amplifying character, and a common connection extending through said sound chamber and its diaphragm to the apex of said cone-shaped diaphragm, means for attaching said diaphragms to said connection, means for detaching said coneshaped diaphragm from said connection, and

an ear reception member connected with said sound chamber.

3. In a radio receiving device, a supporting base, audio receiving mechanism supported upon said base, a cone-shaped diaphragm of an amplifying character having its apex connected with said mechanism and supported from said base, a sound chamber supported by said base on one side of said diaphragm, a flat diaphragm in said sound chamber also connected with said mechanism, a connector carried by said base, and a conduit leading from said sound chamber to said connector, said connector being arranged to receive the tube of an ear reception member.

In testimony whereof, I have hereunto set my hand this 1st day of September 1925.

WILLIAM M. BRUCE, JR. 

